The present invention relates to arc discharge flash lamps and, more particularly, to an improved electrical wiring means for triggering said lamps into a conductive state.
Flash lamps have found use in a variety of applications; photography, electro-photography, optical recording, etc. A lamp comprises two spaced apart electrodes within a sealed glass envelope. The envelope is filled with an inert gas at a subatmospheric pressure. The lamp is connected across a high capacity condenser bank which is charged to a potential just below the ionization level of the gas. Upon application of an additional pulse of voltage (the triggering pulse) the gas is ionized causing the condenser bank to discharge through the tube and resulting in emission of a short, intense light flash.
The triggering pulse may be applied in a variety of ways as disclosed in the prior art. Conventionally, a wire is wrapped around the length of the tube and connected to the electrodes or to a conductive strip positioned on the lamp. U.S. Pat. No. 3,868,182 discloses a trigger wire maintained in a parallel spaced relation to the lamp. The triggering pulse may also be applied internal to the tubes as shown in U.S. Pat. Nos. 3,993,922 and 4,047,064, wherein the trigger wire is embedded within the envelope wall.
The triggering mechanism may be other than a wire configuration; in U.S. Pat. No. 4,156,890 an elongated trigger bar is positioned adjacent the lamp envelope while in U.S. Pat. No. 3,733,599, the lamp is placed adjacent a ground conductive member.
In all of the prior art devices, the lamp must be retained or secured in place by a mounting mechanism. The mechanism may take many forms. Typically, the lamp ends are placed within clamps mounted to a housing frame or to another component, such as a reflector and are coupled to the power source through some form of connector. The triggering device of the present invention is adapted to perform two functions: to provide the required triggering voltage and to secure the lamp in a desired location. The device thus eliminates the need for the aforesaid clamping and connecting mechanisms and provides for a flash lamp assembly which is less costly and easier to assemble and repair.